Opposed piston engine cylinder liner



July 1, 1947.

H. LIEB ERHERR OPIOSED PISTON ENGINE CYLINDER LINER 7 Filed Feb. 16. 1945 UOEUCUOOGQ INVENTOR HAN-5 L/EBERHE'RR BY I . Q j ATTORNEYS Patented July 1, 1947 OPPOSED PISTON ENGINE CYLINDER LINER Hans Lieberherr, Winterthur, Switzerland, assignor to Sulzer Freres, Societe Anonyme, Winterthur, Switzerland Application February 16, 1945, Serial No. 578,262

In Switzerland June '7, 1944 6 Claims.

This invention relates to an opposed-piston internal combustion engine with cooled liners inserted in its cylinders. It consists in that two liners arranged coaxially and each swept by a material.

section.

with outlet ports 9.

of service.

is arranged between the coaxial liners by arranged flanges 6 and I and the centre ring I2, apart from the metallic sealing of the surfaces of contact 29. Both the centre ring I2 and the flanges I5, I are provided in their contact surfaces The cavities I3 arranged in both con- From The centre ring I2 is In this way the working reli- The division of working piston are detachably connected to each 5 other by means of a centre ring inserted between with cavities I3 serving as collecting spaces for their ends with a sealing eflect, the surfaces of cooling medium, which may be designed as ring contact between the liners and the centre ring pa having cavities which serve as collecting spaces tact surfaces of the centre ring I2 are connected for coo-ling medium and communicate with each to each other through a number of passages I i. other and with the hollow cooling spaces provided In order to obtain an increased cooling efiect on between liners and cylinder. the centre piece I'2, the single passages I4 make It is e ped e t to d s gn the cavities provided an angle in axial planes and are thus conducted in the surfaces of contact and serving as collectas near as possible to the dead space 5. ing spaces for cooling medium as ring passages. the cavities I3 of the flanges 6 and I a number For the purpose of obtaining a gastight cylinder of passages I5 lead into the hollow cooling spaces working space it is advantageous to seal the conit provided between th liners I and 2 and the tact surfaces between the coaxial liners and the cylinder 3. The centre ring 12 is further equipped centre ring by means of a packing ring of elastic with the usual fitting bores II for fuel valves,

In order to protect the centre ring starting valves and the like. from the direct radiation of and contact with the In @116 a p S n n F 2 t Centre ri combustion gases, it can be provided with aloose- I2 is provided with a loosely inserted fire proly inserted heat protective ring. tective ring I8, which protects it from the direct Exemplifications of the invention are shown in radiation of and contact with the combustion the attached drawings, Fig. 1 showing a longitugases. 'I h'is protective ring I8 may be made of a dinal section of a first embodiment and Fig. 2 a heat resistant material, for instance a high alloy detail of a second embodiment in longitudinal steel, or of an insulating material, for instance a ceramic substance.

In Fig. 1 the liners I, 2 arranged co-axial in equipped with axially directed cooling passages the cylinder jacket 8 of an opposed-piston en- I4 and also with the usual fitting bores IT for fuel gine working on the two-stroke cycle are swept valves, starting valves, etc, and can otherwise be by the working piston 3 and 4 respectively and of the same design as the centre ring shown in are provided at the end nearest the dead space 5 F g. with flanges 5 and 1 respectively. The liner 2 ar- The present invention offers the advantage ranged on the scavenging side is equipped with that, owing to the provision of intermediate c01- inlet ports III, and the liner I on the exhaust side lecting spaces I3 for cooling medium, the course Between the flanges 6, I of of the cooling-water passages can be chosen in the liners I, 2 the centre ring I2 is inserted and each of the three parts I, 2, I2 independently is detachably connected to the former by means of the other parts and only in the light of its of tie-bolts II. It is expedient for these tie-bolts 4O own requirements, whereby a minimum concen- II to be heldin the flange I of the liner 2 on the tration of stress can be obtained in the single inlet side by a screw connection. In this way, parts I, I2, I2. during overhauls and replacement of the liner I ability is increased, and particularly that of the on the exhaust side, which experience shows to be centre ring I2, which is subjected to the highest subject to the intenser heat stressing and greater pressures at high temperatures. fouling of the two, the tie-bolts II can remain atthe cylinder working space into three parts furtached to the liner 2 on the inlet side in that, ther permits the liners I, 2 to be made of a mateafter the nuts I la have been loosened, the centre rial with good running qualities, while the centre ring I2 and the liner I can be drawn off the bolt ring I2 not swept by the working pistons 3, 4 con- II. Thus the thread of the screw joint is saved sists of a, material which is chosen in the first wear and tear and can be used for a long period place for its appropriate toughness and accordingly has a good notch impact strength, high re- In order to obtain a gastight cylinder working sistance to scaling, corrosion and the like. space for the working pistons 3 and 4, a packing Instead of designing the collecting spaces I3 for cooling medium as uninterrupted ring pasring I9 of elastic material, for instance rubber,

sages, they could be divided up into several spaces and might communicate through passages I4, I5 with the hollow cooling spaces [6. The elastic packing ring I9 supplements the metallic sealing at the sealing surfaces 20 of the flanges 6, T and of the centre ring [2. In particular the packing ring [9 of elastic material prevents the entry of cooling liquid into the cylinder working space, for instance in cases when, as a result of the seizing of the working piston, the tie-bolts H are stretched and consequently the metal sealing at the contact surfaces 20 is temporarily impaired.

I claim:

1. A cylinder for opposed pistons comprising a liner for each piston, a center ring coaxially positioned between the two liners, means for efiecting a gas-tight connection between the liners and the center rin a cooling space at the place of contact between each liner and the center ring, passages in the center ring connecting the two cooling spaces together, a cylinder jacket for each cylinder liner, a cooling space between each liner and its jacket, and passageways connecting each cooling space between the center ring and the linerswith a cooling space between each liner and its jacket.

2. A cylinder for opposed. pistons as defined in claim 1 which comprises cooling spaces between the cylinder liners and the center ring that are formed as ring passages.

3. A cylinder for opposed pistons as defined in claim 1 which comprises packing rings formed of elastic material for efiecting a gas-tight connection between the liners and the center ring.

4'. A cylinder for opposed pistons as defined in claim 1. which comprises coaxial cylinder liners,

a center ring, the interior cylindrical diameter of the center ring being larger than the interior diameters of the liners, and a, heat protecting liner for the center ring having an interior cylindrical diameter approximately the same as that of the liners.

5. A cylinder for opposed pistonsv as defined in claim 1 which comprises several passageways in the center ring connecting the cooling spaces between the liners and the center ring which extend in the longitudinal direction of the cylinder, said passageways being angularly disposed so as to approach most closely the inner wall of the liner at a position near the dead space of,the cylinder.

6. A. cylinder for opposed pistons as defined in claim 1 which comprises means for inserting tiebolts through the center ring with one end attached to one liner and the other end in the coolin space between the other liner and the jacket whereby the nuts for the tie-bolts may be manipulated in the cooling space.

HANS LIEBERHERR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 710,911 Ebbs Oct. '7, 1902 1,086,793 Steinbecker Feb. 10, I914 1,231,903 Junkers July 3, 1917 1,523,453 Scott Jan. 20, 1925" 1,623,639 Setz Apr. 5, 1927' 

